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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/powerpc/platforms/cell/smp.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/powerpc/platforms/cell/smp.c')
-rw-r--r--kernel/arch/powerpc/platforms/cell/smp.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/platforms/cell/smp.c b/kernel/arch/powerpc/platforms/cell/smp.c
new file mode 100644
index 000000000..895560f4b
--- /dev/null
+++ b/kernel/arch/powerpc/platforms/cell/smp.c
@@ -0,0 +1,168 @@
+/*
+ * SMP support for BPA machines.
+ *
+ * Dave Engebretsen, Peter Bergner, and
+ * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
+ *
+ * Plus various changes from other IBM teams...
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/cpu.h>
+
+#include <asm/ptrace.h>
+#include <linux/atomic.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/io.h>
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/paca.h>
+#include <asm/machdep.h>
+#include <asm/cputable.h>
+#include <asm/firmware.h>
+#include <asm/rtas.h>
+#include <asm/cputhreads.h>
+#include <asm/code-patching.h>
+
+#include "interrupt.h"
+#include <asm/udbg.h>
+
+#ifdef DEBUG
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+/*
+ * The Primary thread of each non-boot processor was started from the OF client
+ * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop.
+ */
+static cpumask_t of_spin_map;
+
+/**
+ * smp_startup_cpu() - start the given cpu
+ *
+ * At boot time, there is nothing to do for primary threads which were
+ * started from Open Firmware. For anything else, call RTAS with the
+ * appropriate start location.
+ *
+ * Returns:
+ * 0 - failure
+ * 1 - success
+ */
+static inline int smp_startup_cpu(unsigned int lcpu)
+{
+ int status;
+ unsigned long start_here =
+ __pa(ppc_function_entry(generic_secondary_smp_init));
+ unsigned int pcpu;
+ int start_cpu;
+
+ if (cpumask_test_cpu(lcpu, &of_spin_map))
+ /* Already started by OF and sitting in spin loop */
+ return 1;
+
+ pcpu = get_hard_smp_processor_id(lcpu);
+
+ /* Fixup atomic count: it exited inside IRQ handler. */
+ task_thread_info(paca[lcpu].__current)->preempt_count = 0;
+
+ /*
+ * If the RTAS start-cpu token does not exist then presume the
+ * cpu is already spinning.
+ */
+ start_cpu = rtas_token("start-cpu");
+ if (start_cpu == RTAS_UNKNOWN_SERVICE)
+ return 1;
+
+ status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, lcpu);
+ if (status != 0) {
+ printk(KERN_ERR "start-cpu failed: %i\n", status);
+ return 0;
+ }
+
+ return 1;
+}
+
+static void smp_cell_setup_cpu(int cpu)
+{
+ if (cpu != boot_cpuid)
+ iic_setup_cpu();
+
+ /*
+ * change default DABRX to allow user watchpoints
+ */
+ mtspr(SPRN_DABRX, DABRX_KERNEL | DABRX_USER);
+}
+
+static int smp_cell_kick_cpu(int nr)
+{
+ BUG_ON(nr < 0 || nr >= NR_CPUS);
+
+ if (!smp_startup_cpu(nr))
+ return -ENOENT;
+
+ /*
+ * The processor is currently spinning, waiting for the
+ * cpu_start field to become non-zero After we set cpu_start,
+ * the processor will continue on to secondary_start
+ */
+ paca[nr].cpu_start = 1;
+
+ return 0;
+}
+
+static struct smp_ops_t bpa_iic_smp_ops = {
+ .message_pass = iic_message_pass,
+ .probe = iic_request_IPIs,
+ .kick_cpu = smp_cell_kick_cpu,
+ .setup_cpu = smp_cell_setup_cpu,
+ .cpu_bootable = smp_generic_cpu_bootable,
+};
+
+/* This is called very early */
+void __init smp_init_cell(void)
+{
+ int i;
+
+ DBG(" -> smp_init_cell()\n");
+
+ smp_ops = &bpa_iic_smp_ops;
+
+ /* Mark threads which are still spinning in hold loops. */
+ if (cpu_has_feature(CPU_FTR_SMT)) {
+ for_each_present_cpu(i) {
+ if (cpu_thread_in_core(i) == 0)
+ cpumask_set_cpu(i, &of_spin_map);
+ }
+ } else
+ cpumask_copy(&of_spin_map, cpu_present_mask);
+
+ cpumask_clear_cpu(boot_cpuid, &of_spin_map);
+
+ /* Non-lpar has additional take/give timebase */
+ if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) {
+ smp_ops->give_timebase = rtas_give_timebase;
+ smp_ops->take_timebase = rtas_take_timebase;
+ }
+
+ DBG(" <- smp_init_cell()\n");
+}